As described in the above-identified application, a ski which is released from a ski boot on a slope, e.g. as a result of the fall of a skier, can engage in free flight and travel at high speeds down the slope to pose a danger to other skiers.
For this reason it has been proposed to provide the ski with an automatic brake which is retained in an inoperative position by application of the heel or toe of the ski boot against the ski, thereby holding an actuator against a spring force which tends to bias brake elements into an operative position extending generally transversely to the ski. The actuator may be engaged by the toe or heel of the boot when the latter is properly received in the ski binding.
Such devices are termed hereinafter generically as ski brakes and generally comprise a mounting plate affixed to the upper surface of the ski and carrying an actuator which is biased under a spring force from the inoperative position in which it is held by the ski boot toward an operative position upon release of the ski boot from the ski.
In one such ski brake, which is mounted behind the binding in a bearing or journal arrangement, the pivot axis includes an acute angle with the longitudinal axis of the ski and the spring force is generated by a torsion spring which acts upon a blade-like brake element.
In another conventional construction, leaf springs are secured at their forward ends to the ski and at their rearward ends tend to bend upwardly when they are unloaded, i.e. upon release of the brake by the ski boot. Upon loading by the ski boot, however, these spring elements are urged toward the upper surface of the ski to swing the blades into positions generally parallel to the ski edges as described in Austrian Pat. No. 299,036. Other ski brakes are described in Austrian Pat. Nos. 280,867 and 210,804 although these devices are somewhat more remote in construction from the present invention than even the prior art devices described above and hence require no detailed discussion.
Austrian Pat. No. 405,844 describes a ski brake having a spring which, upon release of an actuator, rotates a shaft extending transversely to the ski about the ski axis to bring the blade into play.
German published application (Offenlegungsschrift) 2,417,279 describes a ski brake which is mounted by a support plate on the upper surface of the ski. In one recess of the support plate a round-cross-section wire is pivotally journaled and is formed as a first pivot shaft. One end of the round-cross-section wire forms a brake spur while another region of the wire is bent into a retaining hoop, the free end of the hoop being formed as a second shaft journaled in a further recess of the support plate.
It is important in this construction that the two journaling recesses in the support plate be exactly parallel, a factor which increases the fabrication cost and causes differences with respect to mounting or operation if not fulfilled. The two journaling recesses impart an elastic prestress to the round-cross-section wire so that the braking spur automatically springs into the operative position when the wire is released by the ski boot.